Field of the Invention
The invention relates to a circuit for displaying operating states of a device.
Modern production processes mostly proceed in a highly automated way. However, it is frequently necessary in this case for the intermediate products, which arise in the individual production steps and are to be further processed, to be removed from a device and be transported further, and for a device following on in the production process to be charged with them. A similar situation applies to the beginning and end of a process: the device used in the production process as the first machine must be charged, and the device used in the production process as the last machine must be discharged. Furthermore, investigations of a random sample nature are also frequently carried out on the respective intermediate products between two production steps, for example in order to be able to ensure the quality of the products to be produced, and/or to be able to determine any deviations from stipulated values which occur in the production process.
Common to all these operations is the need to be able to visualize in some form or other specific operating states in which the respective devices are to be found. For example in the form of optical and/or acoustic signals for operators, or in the form of electric signals which can be automatically further processed, for example by connected computers or controllers for further devices.
A device described in Published, Non-Prosecuted German Patent Application DE 32 24 586 A1 relates to an apparatus for acquiring operating data, which has a display panel via which maintenance staff, for example, make statements referring to operability and further processing of operating data.
Published, Non-Prosecuted German Patent Application DE 33 04 052 A1 sets forth a signaling unit for operating state signals and having a central control device and a plurality of signaling devices connected thereto. The control device generates output signals that specify an operating state.
Published, Non-Prosecuted German Patent Application De 27 52 987 A1 describes a switching configuration for displaying different optical characteristics by display elements disposed on subscriber apparatuses of a telecommunications system. A memory section, a read-out circuit and a demultiplexer are required. Eight address signals serve to drive eight output signals, it being possible to generate four states per output line (for example xe2x80x9cOffxe2x80x9d, xe2x80x9cslow flickeringxe2x80x9d, xe2x80x9cfast flickeringxe2x80x9d, xe2x80x9cpermanently litxe2x80x9d).
As shown in the text book by Don Lancaster and entitled xe2x80x9cDas CMOS-Kochbuchxe2x80x9d[xe2x80x9cThe CMOS Cook Bookxe2x80x9d), IWT-Verlag GmbH, Vaterstetten, it is also possible in principle to have recourse to known elementary exemplary circuits such as 1- from-4 decoders etc. when configuring simple generic circuits for signal processing.
It is accordingly an object of the invention to provide a circuit for displaying operating states of a device that overcomes the above-mentioned disadvantages of the prior art devices of this general type, which detects operating states of a device and provides information on the operating states in a suitable way for further use.
With the foregoing and other objects in view there is provided, in accordance with the invention, an apparatus for displaying operating states of a device, including: a circuit having two input terminals receiving two input signals and three output terminals outputting three output signal including a first output signal, a second output signal and a third output signal each having an activated state and a deactivated state derived from the two input signals; the circuit is configured such that in each case exactly one of the three output signals is activated; during the activated state of the first output signal, the first output signal has a first effective value exceeding a value of a given first reference potential; during the activated state of the second output signal, the second output signal has a second effective voltage value exceeding a value of a given second reference potential; and during the activated state of the third output signal, the third output signal has a value being one of: a third effective voltage value exceeding a value of a given third reference potential; and the third effective value during a first time period, and a fourth effective value that is less than the value of the third reference potential during a second time period, the first time period and the second time period being repeated while the third output signal is in the activated state.
In the case of the circuit according to the invention, it is advantageous to be able to use as input signals of the circuit, signals that are already present in the device whose operating state is to be detected. Furthermore, it is advantageous to be able to indicate the operating state as simply as possible. In this case, it is possible to use further devices for the purpose of indication such as, for example, a computer, acoustic devices such as horns or optical devices, for example in the form of traffic lights. The latter case serves, in particular, to inform operating, maintenance and/or repair staff.
In accordance with an added feature of the invention, at least two of the first effective value, the second effective value, and the third effective value are equal.
In accordance with an additional feature of the invention, at least two of the given first reference potential, the given second reference potential and the given third reference potential are equal.
In accordance with a concomitant feature of the invention, the three output terminals include a third output terminal, and a duration of each of the first time period and the second time period is long enough for reliably detecting and displaying the third effective value and the fourth effective value on a display device that can be connected to the third output terminal and receives the third output signal.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a circuit for displaying operating states of a device, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.